HomeMy WebLinkAboutNelson Meadows Lot 15_Water and Sewer Report
Water and Sewer Memo:
for
NELSON MEADOWS LOT 15
Gallatin County, Montana
September, 2025
Prepared For:
Delesalle Projects Montana INC
Prepared By:
Hyalite Engineers, PLLC
Brett Megaard, PE
Page 1
NELSON MEADOWS LOT 15
ENGINEER’S WATER AND SEWER MEMO
Owner: Delesalle Projects Montana INC
400-1788 W 5th Ave
Vancouver, V6J1P2 BC
Introduction
This report provides an estimate of the peak-hour sanitary sewer demand as well as the
average and max day demands of domestic water usage for the proposed site development.
The City of Bozeman Design Standards and Specifications (March 2004) was used as the
primary guideline for this stormwater drainage design.
General Design
The proposed development of the site will contain three buildings that will connect to city
sewer and water. Proposed building one and three will consist of commercial and residential
units. Proposed building two will consist of commercial units. A proposed 8” water main will
run through the middle of the site and connect to the existing main running down Prince
Lane. From the existing service stubs, building one will have a 2” domestic water service
line, 4” fire line and one new 6” SCH 40 PVC sewer service line. Buildings two and three will
each have one new 2” domestic water service line, 4” fire line and one new 6” SCH 40 PVC
sewer service line. The sewer services will be installed at a minimum slope of 1/8-inch per
foot. Cleanouts will be provided at each bend as well as at the exterior of the building.
Sewer Demands for Building 1
Assuming an average daily flow of 2.17 people per dwelling with 64.4-gallons per capita per
day for residential units:
(2.17 people per dwelling) X (14 dwellings) = 30.38 people
(30.38 people) X (64.4 gallons per person per day) = 1,957 gallons per day
Assuming 12 employees for commercial use with an average daily flow of 13 gpd per
employee:
(12 employees) X (13 gpd) = 156 gallons per day
Assuming 50 customers and 3 employees for a coffee shop with an average daily flow of 6
gpd per customer and 10 gpd per employee:
(50 customers) X (6 gpd) + (3 employees) X (10 gpd) = 330 gallons per day
Using a peaking factor of 4.43 calculated from equation 10-1 from DEQ Circular 2:
(1.70 gpm) X 4.43 = 7.51 gpm
Page 2
Water Demands for Building 1
Assuming 2.17 people per unit with an average daily usage of 170-gallons per person:
(2.17 people per unit) X (14 units) = 30.38 people
(30.38 people) X (170 gallons per day) = 5,165 gallons per day
Using a maximum day to average day ratio of 2.3:1 from City of Bozeman Design Standards:
(5,165 gpd) X 2.3 = 11,880 gallons per day (8.25 gallons per minute)
(Domestic Water Only)
Fire Flow Demand for a Type 1A 17,820 square foot building per the IFC is 1,500 GPM
Total Demand 1508.25 gpm
Sewer Demands for Building 2
Assuming 14 employees for commercial use with an average daily flow of 13 gpd per
employee:
(14 employees) X (13 gpd) = 182 gallons per day
Using a peaking factor of 4.43 calculated from equation 10-1 from DEQ Circular 2:
(0.13 gpm) X 4.43 = 0.56 gpm
Water Demands for Building 2
Assuming 2.00 people per unit with an average daily usage of 170-gallons per person:
(2.00 people per unit) X (7 units) = 14 people
(14 people) X (170 gallons per day) = 2,380 gallons per day
Using a maximum day to average day ratio of 2.3:1 from City of Bozeman Design Standards:
(2,380 gpd) X 2.3 = 5,474 gallons per day (3.80 gallons per minute)
Fire Flow Demand for a Type 1A 13,268 square foot building per the IFC is 1,500 GPM
Total Demand 1503.8 gpm
Sewer Demands for Building 3
Assuming an average daily flow of 2.17 people per dwelling with 64.4-gallons per capita per
day for residential units:
(2.17 people per dwelling) X (14 dwellings) = 30.38 people
(30.38 people) X (64.4 gallons per person per day) = 1,957 gallons per day
Page 3
Assuming 14 employees for a commercial use with an average daily flow of 13 gpd per
employee:
(14 employees) X (13 gpd) = 182 gallons per day
Using a peaking factor of 4.43 calculated from equation 10-1 from DEQ Circular 2:
(1.49 gpm) X 4.43 = 6.60 gpm
Water Demands for Building 3
Assuming 2.17 people per dwelling with an average daily usage of 170-gallons per person:
(2.17 people per dwelling) X (14 dwellings) = 30.38 people
(30.38 people) X (170 gallons per day) = 5,165 gallons per day
Using a maximum day to average day ratio of 2.3:1 from City of Bozeman Design Standards:
(5,165 gpd) X 2.3 = 11,880 gallons per day (8.25 gallons per minute)
(Domestic Water Only)
Fire Flow Demand for a Type 1A 8,952 square foot building per the IFC is 1,500 GPM
Total Demand = 1,508.25 gpm
Sewer Demand Summary
Total Sewer Demand = 4,764 gpd
Allowable Sewer Demand = 5,489.5 gpd (2056 gpa x 2.67 acres)
Appendix A – Residential Water Service
N E L S O N M E A D O W S L O T 1 5
J U N E 2 0 2 5
A P P E N D I X
APPENDIX A
RESIDENTIAL WATER SERVICE
Residential (2018 IRC)
City of Bozeman Water Service Calculation Worksheet
Project Address: ___________________________________ Property Owner: ________________________________
General Contractor: _______________________________________________________________________________
Permit Number: _______________ Proposed Water Meter Size: ______________
UPC Table 610.3 Standard Design Water Supply Fixture Units
Appliances and Fixtures Fixture Units # of Fixtures Total
Bathtub or combo tub/shower (1/2” fill valve) 4.0 X ________ = ________
Bath Tub (3/4” fill valve) 10.0 X ________ = ________
Shower (per head) 2.0 X ________ = ________
Clothes washer 4.0 X ________ = ________
Dishwasher 1.5 X ________ = ________
Hose Bibb 2.5 X ________ = ________
Additional Hose Bibb (each) 1.0 X _______ = ________
Lavatory Sink 1.0 X ________ = ________
Kitchen Sink 1.5 X ________ = ________
Laundry Sink 1.5 X ________ = ________
Water closet [toilet] (1.6 GPF) 2.5 X ________ = ________
Bidet 1.0 X ________ = ________
Urinal (flushometer valve) Table Values* ________ = ________
Total Number of Fixture Units ________
Fixture Unit Tables for Determining Water Pipe & Meter Size Pressure Range – 46-60 PSI
Circle the length in feet to the farthest fixture & applicable service, meter & branch sizes below based on the total number of fixture
units detailed above.
Maximum Allowable Length in feet
Meter & Supply & 60’ 80’ 100’ 150’ 200’
Service Branches
¾” ¾” 20 19 17 14 11
¾” 1” 39 36 33 28 23
1” 1” 39 39 36 30 25
¾” 1¼” 39 39 39 39 39
1” 1¼” 78 76 67 52 44
1½” 1¼” 78 78 78 66 52
1” 1½”/2” 85 85 85 85 85
1½” 1½” 151 151 151 128 105
2” 1½” 151 151 151 150 117
1½” 2” 370 340 318 272 240
2” 2” 370 370 370 368 318
If count is over 370 fixtures, water demand does not meet table 610.4 and must be engineered by a registered Montana
mechanical engineers design, signed and stamped. 04.29.20
Residential (2018 IRC)
City of Bozeman Water Service Calculation Worksheet
Project Address: ___________________________________ Property Owner: ________________________________
General Contractor: _______________________________________________________________________________
Permit Number: _______________ Proposed Water Meter Size: ______________
UPC Table 610.3 Standard Design Water Supply Fixture Units
Appliances and Fixtures Fixture Units # of Fixtures Total
Bathtub or combo tub/shower (1/2” fill valve) 4.0 X ________ = ________
Bath Tub (3/4” fill valve) 10.0 X ________ = ________
Shower (per head) 2.0 X ________ = ________
Clothes washer 4.0 X ________ = ________
Dishwasher 1.5 X ________ = ________
Hose Bibb 2.5 X ________ = ________
Additional Hose Bibb (each) 1.0 X _______ = ________
Lavatory Sink 1.0 X ________ = ________
Kitchen Sink 1.5 X ________ = ________
Laundry Sink 1.5 X ________ = ________
Water closet [toilet] (1.6 GPF) 2.5 X ________ = ________
Bidet 1.0 X ________ = ________
Urinal (flushometer valve) Table Values* ________ = ________
Total Number of Fixture Units ________
Fixture Unit Tables for Determining Water Pipe & Meter Size Pressure Range – 46-60 PSI
Circle the length in feet to the farthest fixture & applicable service, meter & branch sizes below based on the total number of fixture
units detailed above.
Maximum Allowable Length in feet
Meter & Supply & 60’ 80’ 100’ 150’ 200’
Service Branches
¾” ¾” 20 19 17 14 11
¾” 1” 39 36 33 28 23
1” 1” 39 39 36 30 25
¾” 1¼” 39 39 39 39 39
1” 1¼” 78 76 67 52 44
1½” 1¼” 78 78 78 66 52
1” 1½”/2” 85 85 85 85 85
1½” 1½” 151 151 151 128 105
2” 1½” 151 151 151 150 117
1½” 2” 370 340 318 272 240
2” 2” 370 370 370 368 318
If count is over 370 fixtures, water demand does not meet table 610.4 and must be engineered by a registered Montana
mechanical engineers design, signed and stamped. 04.29.20
Residential (2018 IRC)
City of Bozeman Water Service Calculation Worksheet
Project Address: ___________________________________ Property Owner: ________________________________
General Contractor: _______________________________________________________________________________
Permit Number: _______________ Proposed Water Meter Size: ______________
UPC Table 610.3 Standard Design Water Supply Fixture Units
Appliances and Fixtures Fixture Units # of Fixtures Total
Bathtub or combo tub/shower (1/2” fill valve) 4.0 X ________ = ________
Bath Tub (3/4” fill valve) 10.0 X ________ = ________
Shower (per head) 2.0 X ________ = ________
Clothes washer 4.0 X ________ = ________
Dishwasher 1.5 X ________ = ________
Hose Bibb 2.5 X ________ = ________
Additional Hose Bibb (each) 1.0 X _______ = ________
Lavatory Sink 1.0 X ________ = ________
Kitchen Sink 1.5 X ________ = ________
Laundry Sink 1.5 X ________ = ________
Water closet [toilet] (1.6 GPF) 2.5 X ________ = ________
Bidet 1.0 X ________ = ________
Urinal (flushometer valve) Table Values* ________ = ________
Total Number of Fixture Units ________
Fixture Unit Tables for Determining Water Pipe & Meter Size Pressure Range – 46-60 PSI
Circle the length in feet to the farthest fixture & applicable service, meter & branch sizes below based on the total number of fixture
units detailed above.
Maximum Allowable Length in feet
Meter & Supply & 60’ 80’ 100’ 150’ 200’
Service Branches
¾” ¾” 20 19 17 14 11
¾” 1” 39 36 33 28 23
1” 1” 39 39 36 30 25
¾” 1¼” 39 39 39 39 39
1” 1¼” 78 76 67 52 44
1½” 1¼” 78 78 78 66 52
1” 1½”/2” 85 85 85 85 85
1½” 1½” 151 151 151 128 105
2” 1½” 151 151 151 150 117
1½” 2” 370 340 318 272 240
2” 2” 370 370 370 368 318
If count is over 370 fixtures, water demand does not meet table 610.4 and must be engineered by a registered Montana
mechanical engineers design, signed and stamped. 04.29.20